Rin and Seri, Inseparable goes nuts with token generators like Release the Dogs, while Be'lakor, the Dark Master simply triggers more often if you can generate more demons from a single card like Great Unclean One or Demonic Covenant
Pillar Analysis: Unique Effect (Mana Combo), Scarcity (Antiquities, Reserved List), Combo Enabler
The helper card pictured above is an optional game accessory that you can use to give your face-down permanents a little more battlefield presence until you turn them face up
While some will loathe the CGI look of Thalia, this unusually-tight closeup of Thalias eyes and her swords hilt tells a lot about her characters nobility and conviction
Even if that creature is legendary, the Spirits would not enter the battlefield attacking
If you can get the secondary Commander Cayth, Famed Mechanist on the board, she can also tap each turn to Populate (creating a token of another token)